Railway traffic controlling apparatus



June 2, 1931. L. E. SPRAY 1,808,325

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed may 17, 1930 fi iNVENTOR.

1 ,E.5 ra I Patented June 2, 1931 UNITED STATES PATENT LESTER E. SPRAY, or WILKINSBURG, PENNSYLVANIA, 'AssieNoR To THE nNIoN SWITCH &: SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILWAY TRAFFIC CONTROLLING- APPARATUS Application filed May 17, 1930. Serial 1 \To.'453,364.

My invention relates to railway traffic controlling apparatus, and particularly toapparatus of the type involving a railway switch and the signal governing traflic over the switch.

More specifically, my invention relates to the approach locking of a switch, and has for an object the provision of novel and improved approach locking means whereby momentary release of the track relay for the section including the switch will not result in false operation of the approach locking apparatus.

"I will describe two forms of apparatus embodying my invention, and will then point out the novel features thereof i claims.

In the accompanyingdrawings, Fig. l'is a diagrammatic view showing one form of apparatus embodying my invention. Fig. 2 is a diagrammatic view showing a modification of a portion of the apparatus shown in Fig. 1 and also embodying my invention.

Similar reference characters refer to similar parts in each of the views.

'Referring first to Fig. 1, the reference.

characters 1 and l designate the track rails of a stretch of main track A, which rails are divided by insulated joints 2 to form a main section UV, a first approachsection YU, and a second approach section WY. The main section UV is provided with a switch B leadinginto' a side track C. Traflic moving toward the right over switch B is governed by two signals S and S controlled in part by the usual home relays H and H respectively. The switch B is provided with an operating mechanism D, which is controlled in part by a polarized switch relay M. Each track section is providedwith th usual track circuit, comprising a battery '3 connected across the rails'at the right-hand end of the section, and a track relayconnected across the rails at the leftsh'andend of'the section and designated-by the referencev character T with a distinguishing exponent; The first approach section .YU is. provided with an insulated joint 2 near the rightehand end lof the section, and an auxiliary track relay E is connected with the rail 1 on opposite sides ofthis joint. It follows thatrelay E is energized at all timesexcept when some portion of a train occupies the space between the insulated joint 2 and the point U. a

Relay E controls a slow-releasing relay F, the-circuit being from terminal at of a suit' able source'of current, through back contact 4 of relay E, and thewindingof relay F to terminal o of the same source of current.

The reference characterP designates the usual approach locking relay, the circuits and function of which will be explained hereinafter.

Signal S is provided with an operating circuit which includes a front contact 5 of relay H so that this signal can not indicate proceed unless the relay is energized. Signal S is controlled in similar manner by a front contact 6'of relay H Relays H and H are controlled in the usual manner from a distant point, such as an interlocking tower on. despatchers office, and the circuits for these relays include a front contact 16 of trackrelay' T so that-both relays will be deenergized' when a! train occupies the main track secti,on-UV. e The switch operating mechanism is controlled by the polarized switch relay. :M

in such manner that the switch occupies one position orithe otherqacc'ording asrelay M is energized in one direction ,or the other, this controlv being accomplished by a neutralcontact ,18 and apolarized contact 17 ofrelay; M.-;;Thecontrol jof the switch mechanism by relay M forms no part of my present. invention. Relay M. will usual,- ly be controlled'fromthe, same remote point as the signal relays H? andI-P," and the circuit for relay M includes a'front contact 15 of the approach locking relayP, so that relay M cannotbe energizedjto operatethe switch B unless relay is energized.- f i Relay P is-pr'ovicled with a main pick-up circuit which "passes "from terminal wthrough back contact 7 of relay 'H back contact 8 of'relay H front'contact-'-9 -of track relay T front contact 10 of track relay T and the winding of relay P to for said approach section including a source of current connected across the rails at the exit end and an auxiliary relay connected around said joint, a slow-releasing relay controlled by a back contact of said auxiliary relay, an approach locking relay, means for preventing operation of said switch unless said approach locking relay is energized, and a pick-up circuit for said approach locking relay including in series a back contact of said main section track relay and a front contact of said auxiliary relay as well as a front contact of said slow-releasing relay.

2. In combination, a main section of railway track containing a switch, a track circuit including a track relay for said section, an approach section, a track circuit for said approach section including a track relay con-' nected across the rails at the exit end, a slow-releasing relay controlled by a back contact of said approach section track relay, an approach locking relay, means for preventing operation of said switch unless said approach locking relay is energized, and a pick-up circuit for said approach locking relay including in series a back contact of said main section track relay and a front contact an approach section,

of said approach section track relay as well as a front contact of said slow-releasing relay.

3. In combination, a main section of railway track containing a switch, a track circuit including a track relay for said section, a track circuit including a track relay for said approach section, a slow-releasing relay controlled by a back contact of said approach section relay, an approach locking relay, means for preventing operation of said switch unless said approach locln'ng relay is energized, and a pick-up circuit for said approach locking relay including in series a back contact of said main section track relay and a front contact of said approach section relay as well as a front contact of said slow-releasing relay.

In testimony whereof I aflix my signature.

LESTER: E. SPRAY. 

